Manifold implemented in multi-channel system for controlling flow of fluids in oil well

ABSTRACT

Manifold for controlling flow of fluids in multi-channel system deployed in oil well including an orifice formed between inlet ports and outlet ports. The orifice receives fluid through inlet ports and is in fluid communication with a pressure system and tank. The manifold includes a check valve connecting the orifice and receiving/controlling flow of fluid. The manifold includes a gas charged accumulator adapted to store hydraulic energy generated at an inlet of the gas charged accumulator when pressure of the fluid becomes greater than a precharge pressure. The manifold includes a flow control valve connecting the check valve and gas charged accumulator. The flow control valve and gas charged accumulator control the opening of the check valve and prevent improper operation of the manifold. The gas charged accumulator dumps fluid into the tank quickly when the flow control valve moves out of its intended position during a failure of drilling operation.

CROSS REFERENCE TO RELATED APPLICATIONS

This application further claims the benefit of the following non-provisional applications, all of which are here expressly incorporated by reference:

Ser. No. 16/909,974 titled “MANIFOLD IMPLEMENTED IN MULTI-CHANNEL SYSTEM FOR CONTROLLING FLOW OF FLUIDS IN OIL WELL,” filed on Jun. 23, 2020 with Attorney Docket No. CFIN002US0TR; and

Ser. No. 17/324,549, titled “MANIFOLD IMPLEMENTED IN MULTI-CHANNEL SYSTEM FOR CONTROLLING FLOW OF FLUIDS IN OIL WELL,” filed on May 19, 2021 with Attorney Docket No. CFIN002US2.

FIELD OF THE DISCLOSURE

The present disclosure relates generally to multi-channel systems implemented in oil wells; and more specifically to a manifold, as a part of a top drive system, for controlling the flow of fluids therein.

BACKGROUND OF THE DISCLOSURE

A wide variety of drilling rigs and methods are known for drilling oil, gas, and water wellbores in subsurface formations. In many known systems and methods, a single wellbore is drilled with a drilling rig and then, to drill another wellbore, the drilling rig is moved to a new location, often near the drilled wellbore. Such rigs, which implement a top drive system, employ a manifold that controls the flow of fluids from oil wells and directs it through various outlets for disposal, measurements or storage, or to a production line. Usually, manifolds include fluid inlets, control valves, flow meters, and fluid outlets.

Typically, manifolds are used to promote the flow of fluid from the oil or gas wells in compliance with the fluid flow requirements of the project, through a feasible arrangement of various flow paths. In order to control the flow of fluid through them, valves are positioned within the pipe flow paths. These valves can be opened or closed at various times based on requirements.

Conventionally, manifolds are made of aluminum as it is easier to machine due to its high malleability, lower material cost, and lower matching and production costs. However, aluminum manifolds face a common issue of washouts that arises from exposure to constant high flow applications, particularly through small flow paths, drilling paths, and orifices, as fluids erode the soft internals of the manifold block. Furthermore, impacts and vibrations from top drive operations can result in stress fractures or wear along the corners or areas where wall thicknesses can be marginal in an aluminum manifold, thereby further reducing the manifold's longevity and functionality. Finally, aluminum has maximum system working pressure limitations due to the metal's inherent low tensile strength.

One example is disclosed in a U.S. Pat. No. 10,156,095 entitled “Top drive and power swivel with high pressure seals and automatic refilling lubrication reservoir” (the “'095 Patent”). The '095 Patent discloses a top drive or a power swivel with a high pressure wash pipe and seal assembly which receives high pressure drilling fluid from a mud pump and provides high pressure drilling fluid to the drilling fluid side of a dual fluid reservoir. A separating piston in the dual fluid reservoir moves toward the oil side as hydraulic oil is used for lubrication. This dual fluid reservoir with separating piston provides hydraulic oil at drilling mud pressure as required by the set of unique high pressure seals which are continuously lubricated and which generate minimal heat.

Another example is disclosed in a U.S. Pat. No. 6,328,070 entitled “Valve arrangement for controlling hydraulic fluid flow to a subsea system” (the “'070 Patent”). The '070 Patent discloses a valve arrangement for controlling hydraulic fluid flow to a subsea system which includes a plurality of docking modules each having a valve element for controlling the flow of a fluid and a docking module port for fluid flow between the valve element. The valve arrangement additionally includes a manifold having manifold ports of uniform cross-section. The docking modules can be interchangeably mounted to the manifold ports as desired to tailor the valve arrangement for any selected valve operation. The valve arrangement also includes an adapter for alternately sealingly interconnecting a first docking module port which is different in shape or area than the cross section of the uniform size manifold port to any selected manifold port so as to permit sealed fluid flow between the first docking module port and the manifold port in one configuration of the valve arrangement and sealingly interconnecting a second docking module port of a different cross-sectional shape or area than the first docking module port to the same selected manifold port so as to permit sealed fluid flow between a second valve element and the first manifold port in another configuration of the valve arrangement.

Another example is disclosed in a US Patent Application No. 2016/0265288 entitled “Devices and methods for controlling a multi-channel system in a petroleum well” (the “'288 Publication”). The '288 Publication discloses devices and methods for controlling flow through a multi-channel system deployed in a petroleum well. The devices of the invention feature a manifold with a plurality of inlets operably connected to the passageways of the multi-channel system. Individual flows of the multi-phase petroleum fluid from the parallel passageways of the multi-channel system towards the inlets of the manifold are controlled by opening or closing of corresponding stopping valves installed on each inlet or group of inlets. After exiting the inlets through the stopping valves, the flows of the multi-phase fluid are consolidated and directed towards single or multiple outlets of the manifold and ultimately towards the outlet of the petroleum well. Individual opening or closing of the stopping valves has the effect of increasing or decreasing the total cross-sectional area available for producing fluid flow through the well.

Another example is disclosed in a U.S. Pat. No. 10,048,673 entitled “High pressure blowout preventer system” (the “673 Patent”). The '673 Patent discloses a BOP system for use in a high pressure subsea environment, including a BOP stack including a lower marine riser package and a lower stack portion, the lower stack portion having a plurality of BOP rams attached to a subsea wellhead. The system also includes a riser subsystem extending from a drilling vessel to the BOP stack and providing fluid communication therebetween, a ship board subsystem electronically, mechanically, and hydraulically connected to the BOP stack and the riser subsystem to control the functions of the BOP stack and the riser subsystem, and a safety instrumented system having a surface logic solver and at least one subsea logic solver, the safety instrumented system in communication with at least a portion of the BOP rams to act as a redundant control system in case of failure of the ship board subsystem.

The system, devices and methods of the cited documents suffer from one or more limitations of the top drive system as discussed above. Therefore, in light of the foregoing discussion, there exists a need to overcome aforementioned limitations associated with conventional aluminum manifolds for controlling flow of fluids.

BRIEF SUMMARY OF THE DISCLOSURE

In the view of the above problems, the present disclosure provides numerous innovations, improvements, and inventions relating to the development of efficient and long-lasting manifolds for top drive systems.

In one aspect, a manifold implemented in a multi-channel system deployed in an oil or gas well for controlling flow of fluids is provided. The multi-channel system includes a plurality of passageways to convey one or more fluids from the oil well. The manifold includes a body having a plurality of inlet ports and a plurality of outlet ports, and a flow control arrangement provided in the body. The plurality of inlet ports is in fluid communication with the plurality of passageways. The flow control arrangement further includes a channel formed between each one of the inlet ports and one of the outlet ports, and a check valve arranged in the channel at each one of the inlet ports of the body. The channel is adapted to receive fluids through the inlet port of the body creating a differential pressure between the inlet ports and the outlet ports. The check valve is configured to regulate or direct flow of fluids into the channel based on the created differential pressure.

In one or more embodiments, the flow control arrangement of the manifold further includes a filter screen arranged at each one of the inlet ports to restrict impurities from entering the channel.

In one or more embodiments, the check valve within the manifold includes threads formed therein to be engaged with threads formed in the channel proximal to the inlet port therein.

In one or more embodiments, the body of the manifold is made of steel or steel alloy. In particular, the present subject matter provides a manifold block that is first machined, and then plated or coated. The potential coating materials may include zinc-nickel, ceramic, a passivation coating, or any variety of plating processes and approaches for preventing corrosion.

In one or more embodiments, the body of the manifold is fabricated by machining of a single block of steel or steel alloy.

In one or more embodiments, the body of the manifold is made of zinc-nickel plated ductile iron.

In another aspect, a system for controlling the flow of fluids is provided. The system includes a plurality of passageways to transport one or more fluids from the oil well. The system further includes a manifold in fluid communication with the plurality of passageways. The manifold includes a body having a plurality of inlet ports and a plurality of outlet ports, the plurality of inlet ports being in fluid communication with the plurality of passageways, and a flow control arrangement provided in the body. The flow control arrangement includes a channel formed between each one of the inlet ports and one of the outlet ports, and a check valve arranged in the channel at each one of the inlet ports of the body. The channel is adapted to receive fluids through the inlet port of the body creating a differential pressure between the inlet ports and the outlet ports. The check valve is configured to regulate flow of fluids into the channel based on the created differential pressure.

In one or more embodiments, the flow control arrangement further includes a filter screen arranged at each one of the inlet ports to restrict impurities from entering the channel.

In one or more embodiments, the check valve includes threads formed therein to be engaged with threads formed in the channel proximal to the inlet port therein.

In one or more embodiments, the body of the manifold is made of steel or steel alloy.

In one or more embodiments, the body of the manifold is fabricated by machining of a single block of steel or steel alloy. By first machining the single block and then plating or coating the block a superior construction results. Coatings may be applied using zing-nickel, ceramic coating material, a passivation layer, or any number of plating processes that provide corrosion prevention.

In one or more embodiments, the body of the manifold is made of zinc-nickel plated ductile iron.

In essence, therefore, the embodiments of the present disclosure substantially eliminate or at least partially address the aforementioned problems in the prior art by providing a novel design that can be used for the development of durable and efficient manifolds.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present subject matter will now be described in detail with reference to the drawings, which are provided as illustrative examples of the subject matter so as to enable those skilled in the art to practice the subject matter. It will be noted that throughout the appended drawings, like features are identified by like reference numerals. Notably, the FIGUREs and examples are not meant to limit the scope of the present subject matter to a single embodiment, but other embodiments are possible by way of interchange of some or all of the described or illustrated elements and, further, wherein:

FIG. 1 is a schematic illustration of components of a drilling system having a manifold therein, in accordance with an embodiment of the present disclosure;

FIG. 2A is a diagrammatic perspective view of a manifold (such as, the manifold of FIG. 1) employed in the drilling system of FIG. 1, in accordance with an embodiment of the present disclosure;

FIG. 2B is a diagrammatic front view of the manifold of FIG. 2A, in accordance with an embodiment of the present disclosure;

FIG. 2C is a diagrammatic rear view of the manifold of FIG. 2A, in accordance with an embodiment of the present disclosure;

FIG. 2D is a diagrammatic top view of the manifold of FIG. 2A, in accordance with an embodiment of the present disclosure;

FIG. 2E is a diagrammatic bottom view of the manifold of FIG. 2A, in accordance with an embodiment of the present disclosure;

FIG. 2F is a diagrammatic left-side view of the manifold of FIG. 2A, in accordance with an embodiment of the present disclosure;

FIG. 2G is a diagrammatic right-side view of the manifold of FIG. 2A, in accordance with an embodiment of the present disclosure;

FIG. 3A is a schematic illustration of a hydraulic circuit for the manifold of FIGS. 2A-2G as implemented in the drilling system of FIG. 1, in accordance with an embodiment of the present disclosure;

FIG. 3B is a schematic illustration of a section representing a flow control arrangement in the hydraulic circuit of FIG. 3A, in accordance with an embodiment of the present disclosure;

FIG. 4A is a diagrammatic illustration of a check valve implemented in the flow control arrangement of FIG. 3B, in accordance with an embodiment of the present disclosure;

FIG. 4B is a diagrammatic illustration of a channel with the check valve of FIG. 4A arranged therein, as implemented in the flow control arrangement of FIG. 3B, in accordance with an embodiment of the present disclosure;

FIG. 5 is a schematic illustration of a section of the manifold of FIGS. 2A-2G depicting a section of the flow control arrangement therein, in accordance with an embodiment of the present disclosure; and

FIG. 6 is a schematic diagram of an Internal Blowout Preventer (IBOP) circuit, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. It will be apparent, however, to one skilled in the art that the present disclosure is not limited to these specific details.

Reference in this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. The appearance of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Further, the terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. Moreover, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but not for other embodiments.

Certain terminology is used in the following description for convenience only and is not limiting. The words “right,” “left,” “lower,” and “upper” designate directions in the drawings to which reference is made. The words “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the personalized air conditioning system and designated parts thereof. The words “first”, and “second”, are only used to represent a particular entity, and are not used to depict any specific order. The terminology includes the words above specifically mentioned, derivatives thereof and words of similar import.

The present invention provides a system for controlling flow of fluids from an oil or gas well. The present disclosure utilizes an improved manifold and a methodology that can be employed during, for example, well cleanup and flow periods or during other well related procedures. The manifold is both adjustable and calibrated to regulate the flow of well related fluids, such as multiphase production fluids. Additionally, the manifold may be integrated with other components at a surface location in an efficient arrangement that facilitates regulation of fluid flow rates. In one application, the combination of components of the manifold is used to regulate the flow rate of a multiphase fluid before that multiphase fluid enters a separator. Beneficially, in the present disclosure, the manifold is fabricated from a much rigid metallic alloy such as steel, instead of aluminum as in conventional manifold systems. Steel grants the manifolds an enhanced resistance to the washouts, fatigue or stress fractures, stress cracks, and chipping associated with aluminum manifolds. In addition, using a steel-based manifold greatly reduces the risk of accidentally stripping a port and ruining the manifold.

In addition to use in an oil and/or gas field for promoting the flow of fluid from the oil or gas wells in compliance with the fluid flow requirements, the method and system of the present disclosure may be used for other applications. Such other applications may include, for example, heavy construction machines, off-highway equipment etc.

Referring to FIG. 1, illustrated is a schematic illustration of an implementation of a drilling system and a system for controlling flow of fluids employed therein, in accordance with an embodiment of the present disclosure. As shown, drilling system 100 includes tubular drill string 102 suspended from drilling rig 104. Drill string 102 has a lower end which extends downwardly through blowout preventer (BOP) stack 106 and into borehole 108. Drill bit 110 is attached to the lower end of drill string 102. Top drive system 112 is operatively coupled to an upper end of drill string 102 for turning or rotating drill string 102 along with drill bit 110 in borehole 108. BOP stack 106 is coupled to well casing 112 via wellhead connecter 114.

When drilling is stopped (i.e., top drive system 112 is no longer turning drill string 102 and drill bit 110), one or more conventional annular BOPs 113 can be closed to effectively close well bore from the atmosphere. Kill line “A,” couples between fluid injection line “B” via standpipe manifold 116 and conventional BOP stack 106 via kill line valve 118. Kill line “A,” permits fluid communication between conventional surface fluid/mud pump 120 and well bore when kill line valve 122 and valving in standpipe manifold 116 are opened. Thus, while BOP 113 is closed, conventional surface fluid/mud pump 120 may be used to pump fluid from reservoir 122 into borehole 108 via fluid injection line B, standpipe manifold 116, kill line “B”, kill line valve 122, and BOP stack 106. Alternatively, while BOP 113 is closed, conventional surface fluid/mud pump 120 may be used to pump fluid from reservoir 122 into borehole 108 via fluid injection line “B”, standpipe manifold 116, drill string 102 and drill bit 110.

Surface fluid pump 120 pumps fluid from surface fluid reservoir 122 through fluid injection line “B”, through the upper end of drill string 102, down the interior of drill string 102, through drill bit 110 and into a borehole annulus. Choke line “C” couples between conventional BOP stack 106 via choke line valve 124 and surface fluid reservoir 122 via manifold 126. Manifold 126 includes flow control arrangement 128. Flow control arrangement 128 controls flow rate through choke line “C” thereby controlling pressure upstream of flow control arrangement 128.

Referring to FIGS. 2A-2G, illustrated are different views of manifold 200 (such as, manifold 126 of FIG. 1) employed in system 100 of FIG. 1, in accordance with an embodiment of the present disclosure. Throughout the present disclosure, the term “manifold” as used herein refers to a flow-routing hardware with plurality of inlet ports and plurality of outlet ports, which is used to transport fluids and control fluid flow. The different types of manifolds include, but are not limited to production (oil, gas, or condensate), lift, water injection, and mixed (production and water injection). Typically, manifolds are equipment which connect two or more valves of a hydraulic system. A variety of block/isolate valves can be combined in a single body configuration. Each of these valves has a separate opening below in order to connect a pipe. The main body or valve chamber is common to all. Such manifolds commonly include ball, bleed, needle, and vent valves. The use of such manifolds in savings in terms of space and installation costs.

As shown in FIGS. 2A-2G, manifold 200 includes a body 202. According to embodiments of the present disclosure, body 202 of manifold 200 is made of steel or steel alloy. In the present embodiments, body 202 of manifold 200 is fabricated by machining of a single block of steel or steel alloy. Optionally, body 202 of manifold 200 is made of zinc-nickel plated ductile iron. With the present subject matter, manifold 200 may be first machined and then plated or coated. Plating or coatings may be in the form of zinc-nickel, ceramic coating material, a passivation layer, or any number of plating processes capable of preventing corrosion of the manifold steel.

As aforementioned, manifold 200 is implemented in a multi-channel system, such as drilling system 100 of FIG. 1, as deployed in an oil well, for controlling flow of fluids. Herein, the multi-channel system includes a plurality of passageways (not shown) to transport one or more fluids from the oil well.

Referring again to FIGS. 2A-2G, as shown, body 202, of manifold 200, has a plurality of inlet ports 204 and a plurality of outlet ports 206. Herein, the plurality of inlet ports 204 are in fluid communication with the plurality of passageways of the multi-channel system, as discussed in the preceding paragraph. Manifold 200 further includes flow control arrangement (such as, flow control arrangement 300B of FIG. 3B, as discussed later in the description) provided in body 202. Such a flow control arrangement is explained in detail with reference to FIGS. 3A and 3B. Further, as shown, manifold 200 includes a set of multiple valves such as valves 208 and 210. The various components in manifold 200 are arranged as per the design requirement of manifold 200 and space constraints in the drilling system (such as, system 100 of FIG. 1) in which manifold 200 is implemented.

Referring to FIG. 3A, illustrated is hydraulic circuit diagram 300A of manifold 200 of FIG. 2 as implemented in drilling system 100 of FIG. 1, in accordance with an embodiment of the present disclosure. Hydraulic circuit diagram 300A includes one or more power sources, one or more valves, one or more controllers for controlling an operation of the valves, one or more filters, one or more orifices and channels, one or more inlets, one or more outlets and so forth. Referring to FIG. 3B, illustrated is a section representing flow control arrangement 300B in hydraulic circuit diagram 300A of FIG. 3A, in accordance with an embodiment of the present disclosure. Herein, flow control arrangement 300B includes power source 302, check valve 304, channel 306 and filter screen 308.

In one aspect of the present disclosure, a single pressed-in embodiment may include a check valve, orifice, and a filter screen. Other embodiments may further provide two separate components, one may be a thread-in check valve, another may be a one-thread-in filter screen, and a machined orifice for matching performance specifications according to a single-component design. Herein, filter screen 308 is arranged at each one of the inlet ports (such as, inlet ports 204) to restrict impurities from entering channel 306. Throughout the present disclosure, the term “filter screen” as used herein refers to a device that may generally be in the form of a mesh and is used to prevent impurities from reaching the outlet ports thereby ensuring high cleanliness level of the fluid. Moreover, it also ensures reliable operations of subsequent apparatuses used in the system. These screens can be made up of metal, alloys etc.

It may be understood that a valve when employed in a steel-based manifold (such as, manifold 200 of the present disclosure) may not seat properly due to the hard nature of the steel. Such a valve may come unseated and thus may affect the proper functioning of the manifold. This may not be a problem with aluminum-based manifolds as known in the art because, with such manifolds, the valve may be installed by pressing it into the manifold, as the aluminum was malleable enough to conform to the shape of the pressed valve. Some of the existing manifolds employ a particular directional flow valve by Lee® company which has integrated functionalities of a check valve, an orifice drilling, and a last-chance filter screen.

Manifold 200 of the present disclosure reshape one or more ports therein (as discussed in more detail with reference to FIG. 5, later in the description) to enable installation of a fixed orifice (in the form of channel 306), a screen (such as, filter screen 308), and thread-in check valve 304 with suitable operational specifications. Such a distributed arrangement of flow control arrangement 300B, replacing a single press-in seated check valve as in the conventional manifolds, improves the reliability of flow control arrangement 300B.

Referring to FIGS. 4A and 4B, illustrated are schematic representations of components of the flow control arrangement of FIG. 3B, in accordance with an embodiment of the present disclosure. FIG. 4A represents check valve 400A to be implemented in manifold 200 of the present disclosure. Throughout the present disclosure, thread-in check valve 400A as used herein refers to devices whose functions include, but not limited to, allowing free flow in one direction while preventing flow in the reverse direction, and regulating the pressure there through. Check valve 400A may be used to isolate portions of a hydraulic circuit or to provide a free flow path around a restrictive valve. Optionally, check valve 400A may be either manual or hydraulically actuated. Check valve 400A is configured to regulate the flow of fluids into channel 400A based on the created differential pressure. FIG. 4B represents channel 400B into which check valve 400A is fitted in an embodiment. Herein, channel 400B is formed between each one of the inlet ports and one of the outlet ports of the manifold, as discussed. Channel 400B is adapted to receive fluids through the inlet port of the body creating a differential pressure between the inlet ports and the outlet ports. Optionally, channel 400B may be a fixed orifice or a variable orifice.

As may be contemplated from FIGS. 4A and 4B, check valve 400A is arranged in channel 400B at each one of the inlet ports (such as inlet ports 204) of manifold 200. Herein, as may be seen from FIGS. 4A and 4B, check valve 400A is a threaded valve that ensures that check valve 400A is properly fixed into the channel (i.e., channel 306) and eliminates any risk of disengagement of check valve 400A from channel 306 in manifold 200, due to any vibrations, forces or torques induced in flow control arrangement 300B. In the present embodiments, check valve 400A includes threads formed therein to be engaged with corresponding threads formed in channel 400B proximal to the inlet port therein. Such an arrangement ensures that check valve 400A is properly seated in body 202 of manifold 200 and does not get dislocated from its original position due to pressure and constant vibrations in the drilling system (such as, system 100 of FIG. 1).

Referring to FIG. 5, illustrated is a section of manifold (such as, manifold 200) depicting the flow control arrangement implemented therein, in accordance with an embodiment of the present disclosure. As shown, check valve 400A of FIG. 4B is arranged in port 502 of manifold 200; and channel 400B of FIG. 4B forms part of port 504. As shown, there is a cross-drilling connection 506 between port 502 and port 504, and thereby check valve 400A is able to control an inflow of fluids, such as oil, through port 502. As discussed, channel 400B may be a fixed orifice including a filter screen (not shown) arranged at one end, within port 504.

Manifold 200, when implemented in a fluid control and/or regulation system such as drilling system 100 of FIG. 1, improves the efficiency as well as reduces energy costs. Beneficially, manifold 200 introduces shorter path flows which reduce pressure drop and heat fluctuations, improving the overall energy efficiency of system 100 of FIG. 1. Beneficially, manifold 200 also reduces installation costs as well as fluid connections because of a simpler, more compact design. Furthermore, manifold 200 mitigates chances of oil leak due to a lesser number of connections, further reducing the need for upkeep against fatigue, wear and loose joints. Furthermore, manifold 200 being of a small and compact size enables installation thereof in confined spaces of the drilling systems, such as system 100 of FIG. 1 without requiring any significant change in design of system 100.

FIG. 6 shows a schematic diagram of Internal Blowout Preventer (IBOP) circuit 600, in accordance with one embodiment of the present disclosure. IBOP circuit 600 includes hydraulic cylinder 602. Hydraulic cylinder 602 opens or closes the top drive, while the top drive rotates. Hydraulic cylinder 602 connects to rotating link adapter 604. Rotating link adapter 604 connects to rotating head 606 in a closed position. IBOP circuit 600 includes double solenoid valve 608 that connects to solenoid valve 610 (referred as C04). In accordance with the present embodiment, liquid/fluid flows in the direction 612 into IBOP circuit 600. Fluid flows through orifice 614, which is in fluid communication with pressure system 616 and tank 618. The fluid flows through check valve CV4 (such as check valve 400A) in manifold assembly 620. In one example, check valve CV4 and orifice 614 are threaded into position and secured with thread locker such as a Loctite, for example. Further, IBOP circuit 600 includes gas charged accumulator 622 that compresses the gas and stores the energy. A person skilled in the art understands that gas charged accumulator 622 stores hydraulic energy generated at an inlet (not shown) of gas charged accumulator 622 when pressure of the fluid becomes greater than a precharge pressure. IBOP circuit 600 presents flow control valve 624. In one exemplary embodiment, flow control valve 624 includes a check-resistor valve such as FCFA Lee™ check-resistor valve (FCFA). Here, flow control valve 624 includes a check valve and an orifice with a screen. An exemplary construction of flow control valve 624 including check valve 304, channel/orifice 306 and filter screen 308 is shown in FIG. 3A. This is in comparison with known art in which a flow control valve includes check valve, orifice and screen all in one.

In the present disclosure, flow control valve 624 is a part of a timing circuit for the systems of IBOP circuit 600. Flow control valve 624 works in conjunction with gas charged accumulator 622 to control the opening of check valve CV4. Flow control valve 624 and gas charged accumulator 622 control the opening of check valve CV4 and prevent improper operation of IBOP circuit 600 thereby ensuring safe drilling operation.

In case of a failure during the drilling operation, flow control valve 624 moves out of its intended position. Generally, the movement flow control valve 624 is sporadic and is caused due to the tight machine tolerances that are not easy to achieve. Typically, a spacer is used to positively hold it in place, but this is an added cost and can be forgotten/neglected during repair. During failures, flow control valve 624 moving out of position prevents the IBOP from building pressure on the “CLOSE” side, preventing safe drilling operation.

In accordance with the present disclosure, when flow control valve 624 falls out of place, then it allows gas charged accumulator 622 to dump the liquid to tank 618 too quickly via solenoid valve C04. Here, gas charged accumulator 622 bleeds down on a time delay and prevents the pilot-to-close check valve CV4 from opening too soon. This provides more robust installation. In one advantageous feature of the present disclosure, the flow control valve 624 i.e., FCFA relies on special installation tooling and close tolerances to positively stay in position. The installation prevents flow control valve 624 from coming loose in manifold assembly 620. As such, the presently disclosed IBOP circuit 600 offers a hardware solution replacing existing circuit at a much lower cost.

The presently disclosed manifold is made of steel instead of aluminium. As such, the manifold provides strong and dependable control solution that drilling demands. The multi-channel system is machined out of zinc-nickel ductile iron block, which is more durable than the standard aluminium. The manifold made of steel provides the multi-channel system enhanced resistance to the washouts associated with aluminium manifolds. In addition, using a steel based block greatly reduces the risk of accidentally stripping a port and ruining the manifold. The above factors combine to provide a durable and long lasting top drive manifold solution allows to perform drilling operations without worrying about manifold failing.

The foregoing descriptions of specific embodiments of the present disclosure have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiment was chosen and described in order to best explain the principles of the present disclosure and its practical application, to thereby enable others skilled in the art to best utilize the present disclosure and various embodiments with various modifications as are suited to the particular use contemplated. 

What is claimed is:
 1. A manifold, comprising: an orifice formed between inlet ports and outlet ports, wherein said orifice receives fluid through inlet ports, and wherein said orifice is in a fluid communication with a pressure system and a tank; a check valve connecting said orifice, wherein said check valve receives and controls the flow the fluid; a gas charged accumulator adapted to store hydraulic energy generated at an inlet of said gas charged accumulator when pressure of the fluid becomes greater than a precharge pressure; and a flow control valve connecting said check valve and said gas charged accumulator, wherein said flow control valve and said gas charged accumulator control the opening of said check valve and prevent improper operation of said manifold, and wherein said gas charged accumulator dumps the fluid into said tank quickly when said flow control valve moves out of its intended position during a failure of drilling operation.
 2. The manifold of claim 1, wherein said gas charged accumulator dumps the fluid into said tank quickly via a solenoid valve.
 3. The manifold of claim 1, wherein said gas charged accumulator bleeds down the fluid on a time delay and prevents said check valve from opening too soon.
 4. The manifold of claim 1, wherein said flow control valve is a check-resistor valve.
 5. The manifold of claim 1, wherein said flow control valve further comprises a check valve and an orifice with a screen.
 6. The manifold of claim 1, wherein said manifold is made of steel or steel alloy.
 7. The manifold of claim 1, wherein said manifold is fabricated by machining of a single block of steel or steel alloy.
 8. The manifold of claim 1, wherein said manifold comprises a coating from a group consisting of a zinc-nickel plated ductile iron, a ceramic coating, a passivation layer or a corrosion prevention layer.
 9. A method of providing a manifold, said method comprising steps of: providing an orifice formed between inlet ports and outlet ports, said orifice receiving fluid through inlet ports, said orifice in a fluid communication with a pressure system and a tank; providing a check valve connecting said orifice, said check valve receiving the fluid; providing a gas charged accumulator adapted to store energy; providing a flow control valve connecting said check valve and said gas charged accumulator; controlling the opening of said check valve and preventing improper operation of said manifold using said flow control valve and said gas charged accumulator control; and operating said gas charged accumulator for dumping the fluid into said tank quickly when said flow control valve moves out of its intended position during a failure of drilling operation.
 10. The method of claim 9, further comprising dumping the fluid into said tank quickly via a solenoid valve.
 11. The method of claim 9, further comprising bleeding down the fluid from said gas charged accumulator on a time delay for preventing said check valve from opening too soon. 